#include <stdio.h>  
#include <math.h>  

int main() {
    int n, j, k;
    for (n = 2; n <= 100; n++) 
        { 
        if (n <= 3) {  
            printf("%d is a prime number\n", n);
            continue;
        }
        if (n % 2 == 0) continue; 
        k = sqrt(n);
        for (j = 3; j <= k; j += 2) {
            if (n % j == 0) break; 
        }
        if (j > k) {  
            printf("%d is a prime number\n", n);
        }
    }
    return 0; 
}
